Effect of vitamin E injection on cortisol and white blood cell response to surgical stress in dairy cows.

In 20 dairy cows the effect of a single vitamin E injection on cortisol and white blood cell response to surgical stress was investigated. Abdominal surgery (omentopexy) was carried out in order to correct a left abomasal displacement. Ten hours prior to surgery 10 cows were injected intramuscularly with 10 mg DL-alpha-tocopheryl acetate per kg body weight. Ten cows (controls) received an equivalent volume of injectable water. Over a 72 hour period plasma samples were collected. In 8 cows (4 cows from each group) alpha-tocopherol in liver tissue was determined. Plasma vitamin E concentrations were significantly higher in vitamin E injected cows than in controls in all of the samples after the vitamin E injections. Similarly, liver alpha-tocopherol concentrations were significantly higher in vitamin E injected cows than in controls. The surgical stress led to profoundly increased plasma cortisol levels and leucocytosis due to neutrophilia within 5 hours after the surgery. Plasma cortisol levels as well as leucocyte counts were not affected by route of vitamin E administration used.